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Silver Nanoparticle-Embedded Thin Silica-Coated Graphene Oxide as an SERS Substrate.

ABSTRACT: A hybrid of Ag nanoparticle (NP)-embedded thin silica-coated graphene oxide (GO@SiO?@Ag NPs) was prepared as a surface-enhanced Raman scattering (SERS) substrate. A 6 nm layer of silica was successfully coated on the surface of GO by the physical adsorption of sodium silicate, followed by the hydrolysis of 3-mercaptopropyl trimethoxysilane. Ag NPs were introduced onto the thin silica-coated graphene oxide by the reduction of Ag? to prepare GO@SiO?@Ag NPs. The GO@SiO?@Ag NPs exhibited a 1.8-fold enhanced Raman signal compared to GO without a silica coating. The GO@SiO?@Ag NPs showed a detection limit of 4-mercaptobenzoic acid (4-MBA) at 0.74 ?M.

SUBMITTER: Pham XH

PROVIDER: S-EPMC5245191 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Silver Nanoparticle-Embedded Thin Silica-Coated Graphene Oxide as an SERS Substrate.

Pham Xuan-Hung XH Hahm Eunil E Kim Hyung-Mo HM Shim Seongbo S Kim Tae Han TH Jeong Dae Hong DH Lee Yoon-Sik YS Jun Bong-Hyun BH

Nanomaterials (Basel, Switzerland) 20160922 10

A hybrid of Ag nanoparticle (NP)-embedded thin silica-coated graphene oxide (GO@SiO₂@Ag NPs) was prepared as a surface-enhanced Raman scattering (SERS) substrate. A 6 nm layer of silica was successfully coated on the surface of GO by the physical adsorption of sodium silicate, followed by the hydrolysis of 3-mercaptopropyl trimethoxysilane. Ag NPs were introduced onto the thin silica-coated graphene oxide by the reduction of Ag⁺ to prepare GO@SiO₂@Ag NPs. The GO@SiO₂@Ag NPs exhibited a 1.8-fold ...[more]

PMID: 28335304

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